Device for coupling a coolant duct of a rotating part

ABSTRACT

A device for coupling a coolant duct of a rotating part, especially for a back-up or transport rollers, includes a hollow resilient compensator device fixedly connected to a journal of the rotating part, wherein the journal comprises a bore hole for conducting a coolant and is insertable in a bearing of a stationary part. A second end of the compensator is connected to a first sealing ring. The compensator is enclosed by a receptacle sleeve which includes a second sealing ring that creates a sealin contact with the first sealing ring. The receptacle is connected to the stationary part at an adjustable distance wherein a pretensioning exerted on the compensator by the receptacle sleeve via the first and second sealing rings is adjustable in response to a distance of the receptacle sleeve from the stationary part.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates is directed to a device for coupling the coolantduct of a rotating part.

2. Description of the Prior Art

Reference DE-PS 42 07 042 discloses a generic device for coupling thecoolant duct of a back-up and transporting roll. This device issupported by pins in bearing blocks or pillow blocks by roller bearings,and coolant flows through the device along an axial bore hole that isguided through the pins. Every bearing block is closed by a cover. Thecover has a cooling duct which is connected at one end to a coolantinlet and coolant outlet, respectively. The other end opens into theregion of the pin bore hole. A compensator is arranged between the ductopening of the cover and the bore hole of the roll and cooperates with aseal which coaxially contacts a sealing face arranged relative to theroll shaft. The seal is preferably constructed as a lip seal.

It is disadvantageous in this construction that the sealing lip of thesealing ring is subject to wear because of the movement occurring on itand therefore has a limited life. Further, the attainable temperaturerange is limited because lip sealing rings are usually made fromelastomers. Moreover, the compensator cannot be pretensioned in adeliberate manner, so that it is not possible to adapt to differentinternal pressures of the coolant.

SUMMARY OF THE INVENTION

It is the object of the invention to provide a long-lasting device ofthe generic type by which the described disadvantages of the prior artare avoided. This object is met by a device for coupling the coolantduct of a rotating part which is rotatably supported in a bearing by ajournal. The journal is connected to a cooling duct which connects abore hole through the journal to an inlet or an outlet for the coolant.A resilient compensator is arranged between the coolant inlet or outletand the bore hole of the journal to prevent motion between the journaland stationary parts. The end of the compensator facing the journal isrotatably fixed by connection to the journal. The end of the compensatorthat is remote from the rotating part is rotatably fixed to a slidingring of a sliding ring seal. A stationary sliding ring of the slidingring seal is supported on a receptacle sleeve which is detachablyconnected to the frame part and encloses the compensator. The positionof the receptacle sleeve with respect to the journal is changeable tosuitably pretension the compensator.

This object is met by the features indicated in the characterizing partof claim 1. Advantageous further developments are contained in thesubclaims.

The advantage of the suggested construction consists in that the rangeof use can be considerably increased through the use of an axiallyacting sliding ring seal. The temperature limitation which was formerlycustomary due to the use of an elastomer for the lip seal is eliminatedin this case. The service life of the device is significantly extended,since the rate of wear of a sliding ring seal is substantially lowerthan that of a lip seal. The hard, wear-resistant material used for thesliding ring seal, e.g., silicon carbide, is capable of pulverizingparticles of dirt that may be carried along by the coolant. Thearrangement of the compensator together with the sliding ring seal in areceptacle sleeve enables the pretensioning by varying the distance ofthe cover-like flange from the frame element of the bearing of therotating part. This varying of pretensioning is used advantageously toadapt the action of the internal pressure of the coolant to the actionof the compensator.

The suggested device may be adapted for use in both high-speed andlow-speed rolls, rollers or the like, by the choice of material as wellas by the size of the sealing surface of the sliding ring seal. Possibleleakage of the coolant in the area of the sliding ring seal is easily beremoved through an opening arranged, for example, in the cover-likeflange. This prevents the undesirable mixing of the coolant with thelubricant for the bearing. In many cases, it is also desirable in theevent of damage to the seal to remove the coolant at a defined locationin a controlled manner to avoid wetting the product produced in theinstallation.

The newly developed construction is also usable for rotating parts inwhich one side is not available for a cooling connection, for example,because of the connection of a drive unit. In this case, the dualprinciple is applied, wherein both the feed and discharge of theselected coolant are carried out from one side. For this purpose, a pipeis arranged in the bore hole of the rotating part, wherein the outerdiameter of the pipe is smaller than the inner diameter of the borehole. This pipe extends through the compensator and the sliding ringseal and is connected with an inlet and outlet connection arranged inthe receptacle sleeve.

DESCRIPTION OF THE DRAWINGS

In the drawing, wherein like reference characters denot similar elementsthroughout the several views;

FIG. 1 shows a partial longitudinal section through a first embodimentform of the device according to the invention;

FIG. 2 shows the device of FIG. 1 as viewed in direction X from FIG. 1;

FIG. 3 shows a partial longitudinal section of a second embodiment formof the device according to the invention

FIG. 4 shows the device of FIG. 3 as viewed in direction Y of FIG. 3;

FIG. 5 shows a third embodiment form of the device according to theinvention in longitudinal section comparable to FIG. 1;

FIG. 6 shows a fourth embodiment form of the device according to theinvention in longitudinal section comparable to FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A first embodiment form of the device according to the invention isshown in FIG. 1 in partial longitudinal section and in FIG. 2 in a viewin direction X of FIG. 1. The end region of a journal 1 of a rotatingpart, not shown in more detail, is covered by a frame part 2 of abearing, not shown more fully, with a seal 3 positioned between theframe part 2 and journal 1. The journal 1 has an axially extending borehole 4 through which the coolant is guided. A recess 5 is arrangedcentrally in the end area of the journal 1. Collar sleeve 7 having athreaded portion 6 is screwed into the recess 5. The collar sleeve 7 hasa collar-shaped neck 8 serving as a stop. This collar-shaped neck 8 ispreferably provided with two flattened portions (not shown), so that asuitable wrench may be applied for tightening the collar sleeve 7.Instead of collar sleeve 7, a flange mounted sleeve may also be used. Afirst end 10 of a compensator 11 facing the frame part 2 is attached,for example, by means of a weld, to a front end 9 of the collar sleeve 7so that the compensator 11 is fixed with respect to rotation relative tothe collar sleeve 7. A second end 12 of the compensator 11 is connectedwith a sliding ring 13 of a sliding ring seal 40 so as to be fixed withrespect to rotation relative to the compensator 11, for example, by aweld. A stationary sliding ring 14 of the sliding ring seal 40 isarranged on a base-like shoulder 15 of a receptacle sleeve 16 so thatthe stationary sliding ring 14 is fixed with respect to rotationrelative to the receptacle sleeve 16, for example, by friction settingor by being pressed into the base-like shoulder

The sliding rings 13, 14 of the sliding ring seal 40 are preferably madeof silicon carbide and are accordingly hard and resistant to wear. InFIG. 1, the receptacle sleeve 16 has a bore hole 18 provided with athreaded portion 17. A corresponding coolant line can be screwed intothis threaded portion 17. Of course, this connection can also bedesigned differently without departing in any way from the essence ofthe invention. At the end facing the rotating part, the receptaclesleeve 16 has a neck 19 extending radially outward. A cover 20 rests onthis neck 19. In this embodiment example, the cover 20 has four boreholes 21, 21', 21", 21'" through which connection screws 22, 22', 22",22'" can be inserted. The cover 20 is fastened to the frame part 2 bythe screws 22 to 22'". The smaller the selected thickness 23 of thecover 20, the higher the pretensioning of the compensator 11 enclosed bythe receptacle sleeve 16. The pretensioning can be reduced by arrangingspacers such as washers, (not shown) between the cover 20 and the framepart 2. In FIG. the coolant flows through the device from left to right,for example, as shown by arrow 24. The coolant also flows through thecompensator 11 which is acted upon by the internal pressure of thecoolant. The allotted pretensioning of the compensator 11 and theinternal pressure of the coolant work together in such a way that theforce required for the sealing effect is achieved.

FIGS. 3 and 4 show a second embodiment form of the device according tothe invention in the same partial longitudinal section and view as inFIG. 1 and FIG. 2, respectively, wherein the same reference numbers havebeen used for identical parts. In contrast to FIG. 1, a plate 25 havingtwo bore holes 21 & 21' and which cooperates with the neck 19 of thereceptacle sleeve 16 is used instead of the cover 20. The distanceaffecting the pretensioning of the compensator 11 is adjusted in thisexample by means of the spacer sleeves 26, 26' enclosing the connectionscrews 22, 22' which are inserted though the two bore holes 21 & 21'.Since the space between the plate 25 and journal 1 is adjustable in thiscase, a seal 27 is arranged between the collar sleeve 8 and thereceptacle sleeve 16 and is secured by a snap ring 28. If a drainageopening is required in this embodiment, it may be arranged in thecylindrical part of the receptacle sleeve 16.

FIG. 5 shows another embodiment example in the same partial longitudinalsection as FIG. 1. In this case also, identical parts are provided withthe same reference numbers. This embodiment form is required when theother side of the rotating part, (not shown) can not accommodate acoolant connection because, for example, the drive for the rotation ofthe rotating part is attached on this side. In this embodiment, a pipe29 which has an outer diameter smaller than the inner diameter of thebore hole 4 of the journal 1 is arranged in the bore hole 4 of thepin 1. This pipe 29 extends through the collar sleeve 7, the compensator11, and the sliding ring seal 40 and is fastened in a differentlydesigned receptacle sleeve 30. This receptacle sleeve 30 differs fromthat shown in FIG. 1 in that it has an inlet connection 31 and an outletconnection 32. The two connections 31, 32 may exchange functions. Theopen end of the receptacle sleeve 30 is closed by a cover 33. The effectof the sliding ring seal 40 in composite action with the compensator 11is the same as was described above.

FIG. 6 shows a second variant which is the counterpart of FIG. 3 inrelation to FIG. 1 which also includes an inlet connection 31 and anoutlet connection 32 in the receptacle sleeve 32. In this embodimentexample also, the cover 20 is replaced by a plate 25 shaped likeeyeglasses and spacer sleeves 26, 26'b cooperating therewith.

We claim:
 1. A device for coupling a duct to a rotary element forconducting a liquid through said rotary element wherein said rotaryelement comprises journals which are receivable in bearings of astationary part for supporting said rotary element, said devicecomprising:a resilient hollow compensator having a first end and asecond end arranged adjacent a bore hole in one of the journals of saidrotary element such that said bore hole and said compensator compriseone continuous passage, said first end of said compensator being fixedlyconnected to said journal such that said compensator is rotatably fixedwith respect to said rotating element; a first sliding ring fixedlyconnected to the second end of said compensator; a receptacle sleevefixedly connected to the stationary part and enclosing said compensator,wherein said receptacle sleeve is connected to said duct and a distancebetween said receptacle sleeve and said stationary part is adjustablevia spacer elements between said receptacle sleeve and said stationarypart; and a second sliding ring fixedly connected to said receptacle forsealingly contacting said first sliding ring and pretensioning saidcompensator; wherein said duct is connected to said bore hole in saidjournal via said receptacle sleeve, said first and second sealing rings,and said compensator and an amount of pretensioning applied to saidcompensator is variable in response to the adjustable distance of saidreceptacle sleeve from said stationary part.
 2. The device of claim 1,wherein said receptacle sleeve comprises a neck portion at an end ofsaid receptacle facing said stationary part and said device furthercomprises a flange fixedly connected by connecting elements to saidstationary part and holding said neck portion of said receptacle sleeve.3. The device of claim 2, wherein said spacer element comprise spacersleeves which enclose connecting elements connecting the flange to thestationary part and said flange comprises a plate spaced from thestationary part by said spacer sleeves.
 4. The device of claim 1,further comprising a collar sleeve fixedly connected between said firstend of said compensator and said bore hole of said journal.
 5. Thedevice of claim 1, wherein said first and second sliding rings comprisea hard, wear-resistant material.
 6. The device of claim 5, wherein saidhard, wear-resistant material comprises silicon carbide.
 7. The deviceof claim 1, wherein said receptacle comprises an inlet duct connectionand an outlet duct connection and said device further comprises a pipehaving a smaller diameter than said compensator and said bore hole,wherein said pipe connects one of said inlet duct connection and saidoutlet duct connection to said rotary element and a space surroundingsaid pipe in said receptacle is in communication with the other one ofsaid inlet duct connection and said outlet duct connection.
 8. Thedevice of claim 4, further comprising a sealing ring sealingly connectedbetween said receptacle and said collar sleeve.
 9. The device of claim1, wherein said receptacle comprises a flattened portion cooperatingwith said connection to said stationary portion for preventing rotationof said receptacle portion with said journal.